Frame or yoke for dynamo-electric machines



No. 627,488. Patentd June 27, I899.

. A. ECK.

FBAIE. 0R YOKE YNAMO ELECTRIC MACHINES.

(A mun mm 1.791;. as, 1899.)

(No Model.)

UNITED STATES PATENT OFFICE.

CHARLES A. EOK, OF NEWARK, NEW JERSEY.

FRAME OR YOKE FOR DYNAMO-ELECTRIC MACHINES.

SPECIFICATION forming part of Letters latent No. 627,488, dated June 27, 1899. Application filed February 25, 1899. Serial No. 706,838. (No model.)

' ject of the King of Sweden and Norway, re-

siding at Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Frames or Yokes for Dynamo-Electric Machines, of which the following is a specification.

Myinvention relates generally to irnprovements in dynamo-electric machines, and particularly to the frame or yoke part of electrical dynamos and motors.

Hitherto it has been necessary to cast frames or yokes in several parts in order to admit of the introduction of field-coils and to rivet or otherwise fasten the pieces together after the parts utilized in providing the field have been placed in position. It is obvious, however, th at a good deal of time and labor are expended in finishing the contact edges of the several parts so as to make them fit snugly, and the resultant frame or yoke, even when its component parts are fitted nicely together, does not afford an unimpaired circuit for the magnetic currents. To obviate this defect and to reduce the cost of manufacture are the objects of my invention. As the lines of magnetic force act in continuous curves, it has been found by experience that a spherical frame or yoke is conducive to a higher working efficiency. For this reason I believe the above objects to be best attained by the device shown in the accompanying drawings, in which- Figure l is a view in elevation of my frame or yoke; Fig. 2, a transverse sectional view on line a 00 of Fig. 1. V

Similar letters of reference indicate corresponding parts in both views.

I shall describe a frame or yoke of a dynamoelectric machine embodying my invention and afterward point out the novel features in the claims.

A is the yoke or frame.

B B are the two poles, around which the field-coils C O are placed.

D is a hole formed in the yoke A, having its axis coincident with that of a second hole E. The hole D will generally be round, whereas the hole E is bounded by two surfaces G G, in this case arches of the same periphery, two semicircular surfaces F F lying at right angles to the surfaces G G and joined to these by straight surfaces H. The object of this peculiar elongated construction of the hole E is to permit the field-coils to be introduced into the yoke and placed in position, thus admitting of the yoke being cast in one piece and affordinga circuit for the magnetic currents in which disturbance by mechanical imperfections has been reduced to a minimum. Such imperfections are well illustrated in a yoke consisting, for instance, of two hollow hemispheres. In this case there will be a leak in the circuit along the line of contact between said hemispheres, thus depreciating the value of the motor. It will therefore readily be seen that my invention will enable the motor or dynamo to do more work, while at the same time the cost of its manufacture will be reduced by reason of the fact that one casting is substituted for two or more.

After the coils are in position the armature and shaft for carrying same are attached by means of bearings of the usual character lying around the holes D and E and secured on the outside of the yoke.

Having thus described my invention, what I claim is 1. In a yoke or frame of the character set forth, the combination with the wall of said yoke of a hole of substantially the same size as the field-coils in said yoke, substantially as described.

2. In a yoke or frame of the character set forth, the combination with. the wall of said yoke of a shaft-hole, asecond shaft-hole whose axis coincides with the axis of the first shafthole, and auxiliary holes formed in said wall, communicating with the second shaft-hole, permitting the admission of field-coils into the yoke, substantially as described.

3. In a yoke or frame of the character set forth, the combination with the wall of said yoke of a central hole and auxiliary holes, formed in said wall, communicating with the central hole, permitting the admission of fieldcoils into the yoke, substantially as described.

In testimony that I claim the foregoing I have hereunto set my hand this 23d day of February, 1899.

CHARLES A. ECK. \Vitnesses:

OTTO FRIDLUND, AXEL V. BEEKEN. 

